Transverse sliding breech block

ABSTRACT

A piece of ordnance having a barrel and breech block that are slidably mounted on a cradle to allow for rearward movement due to recoil and subsequent forward or counter-recoil movement. The breech block is raised during the counter-recoil of the barrel by means of a camming arrangement which includes lateral cam surface means arranged on the cradle and increasing in height in forward direction and cam follower means carried by the breech block and coacting with the cam surface means.

United States Patent [1 1 ornteck et a1.

1 Feb. 18,1975

TRANSVERSE SLIDING BREECH BLOCK Inventors:

Assignee:

Filed:

Appl. No;

Josef Hornfeck, Dusseldorf; Rolf Bartolles, Wuppertal-Vohwinkel, both of Germany Rheinmetall GmbH, Dusseldorf, Germany Dec. 5, 1968 Foreign Application Priority Data Dec. 5, 1967 U8. C1. 89/4 B, 89/24, 89/4, 89/5 Int. Cl F4lf 11/00 Field of Search 89/4 B, 24, 167; 42/14, 42/15 References Cited UNITED STATES PATENTS Germany 1578049 Voller a 89/4 B 1,359,454 11/1920 Adelman et a1 89/4 B l.651,l28 11/1927 Jervey 1. 89/167 X 2,339,661 1/1944 Swartz v l 89/167 3362292 1/1968 DAntlrea v 89/24 3.399.598 9/1968 Hornfeck c1211 119/24 Primary Examiner-Stephen C. Bentley Attorney, Agent, or Firm-Spencer & Kaye [57] ABSTRACT A piece of ordnance having a barrel and breech block that are slidably mounted on a cradle to allow for rearward movement due to recoil and subsequent forward or counter-recoil movement. The breech block is raised during the counter-recoil of the barrel by means of a camming arrangement which includes lateral cam surface means arranged on the cradle and increasing in height in forward direction and cam follower means carried by the breech block and coacting with the cam surface means.

10 Claims, 5 Drawing Figures PATENTED FEB 1 8 I975 SHEET 2 BF 3 TRANSVERSE SLIDING BREECII BLOCK BACKGROUND OF THE INVENTION block that moves in a direction transverse to the bore axis and in the vertical longitudinal central plane of the barrel.

Modern pieces of ordnance are called upon to fire at long range and at a high firing rate, which makes it necessary for ordnance designers to increase the strength of both the breech of the barrel as well as the breech block. This, however, means that these parts have to be made larger, and the resulting increased axial dimensions as well as the increased weight create problems insofar as transportability of the piece and its handling characteristics are concerned. Moreover, the fact that the breech and breech block are larger and heavier makes it more difficult to achieve a high firing rate, particularly since good performance in this respect can be achieved only by using automatic loading mechanisms. These, in turn, take up considerable space behind the breech, so that, particularly when the gun is to be fired at a high angle of elevation, suitable provision has to be made to allow the recoil movement to carry below the surface on which the gun stands.

It is, therefore, the primary object of the present invention to provide a piece of ordnance whose breech mechanism can be built more compactly than that of other guns of comparable caliber, which piece of ordnance can, moreover, operate at high angles of elevation without encountering the drawbacks of heretofore- BRIEF DESCRIPTION OF THE INVENTION With the above object in view, the present invention resides, basically, in a piece of ordnance which includes a barrel having a breech with a breech opening, and a breech block for closing the breech opening. The breech block is mounted for sliding movement relative to the barrel transversely to the axis of the barrel and in the vertical longitudinal central plane of the barrel. The barrel and breech block are mounted on a cradle which allows forward and rearward movement in the direction of the bore axis. Camming means are provided for raising the breech block and thereby uncovering the breech opening during forward, i.e., counterrecoil, movement of the barrel, these camming means including lateral cam surface means on the cradle which increase in height in forward direction, and cam follower means carried by the breech block and coacting with the cam surface means.

By virtue of such an arrangement, the breech mechanism may be made smaller than in the case of pieces of comparable size which incorporate heretofore known types of breech mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of a piece of ordnance according to the present invention, the breech block being shown in open position.

FIG. 2 is a perspective view, partly in section, showing the parts in the same position as depicted in FIG.

FIG. 3 is a side elevational view showing the connection between the breech block and the breech.

FIG. 4 is a rear end view of the parts depicted in FIG. 3.

FIG. 5 is a sectional view taken on line V-V of FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings and first to FIGS. 1 and 2 thereof, the same show a piece of ordnance such as a gun having a barrel 1 which, by means of a sleigh 2, is slidably mounted on the guide rails of a troughshaped cradle 3. The barrel is moved forward into its firing position by means of a conventional counterrecoil mechanism or recuperator (not shown) which engages a flange 4a of the breech 4, the latter being forged to the barrel 1. The breech is engaged by a breech block 5 which uses the surfaces of the breech 4 as a guide surface and which closes the breech end of the bore against the force of the propellant charge, the breech block 5 being slidable relative to the barrel transversely to the bore axis and in the vertical longitudinal central plane of the barrel.

The breech block 5 has laterally extending guide rollers 6 which coact with two cam surfaces 8, the latter constituting the upper surfaces of two side pieces 7 which are attached to the cradle 3, the configuration of the cam surfaces being such that when the barrel is moved forward during counter-recoil, the breech block 5 is raised with respect to the breech 4, thereby opening the breech end of the bore. Each of the cam surfaces 8 itself comprises a short level section 8a at the rear end of the cam surface 8, i.e. that end of the cam surface which faces away from the direction in which the piece fires. The section 8a is parallel to the upper edge of the guide rails afforded by the cradle 3. The section 8a joins an intermediate section 8b which increases in height in forward direction, this section 8b being next to an abruptly downwardly dropping forward section 80. Each side piece 7 is additionally provided with a rectilinear level guide groove 9 which opens inwardly. It is through these guide grooves 9 that the rollers 6 pass when the barrel moves rearwardly during recoil. The lower edge of each guide groove 9 is parallel to the upper edge of the guide rails afforded by the cradle 3 and transitions into the respective rear section 8a. Inasmuch as the cam surface 8 and the guide groove 9 intersect each other, that portion of the intermediate section 811 which extends from the juncture with section 8a to a point above the upper edge of the guide groove 9 is fashioned as a separate subsection 8d which functions as a switch; this is done, in the illustrated embodiment, by providing a pivot joint 10 which allows sub-section to pivot upwardly when the respective roller 6 moves rearwardly through the groove 9.

The breech block 5 itself is connected to the breech 4 by means of two levers l5 and 16 whose upper ends have heads that move in grooves formed by the rails 17 and 18 that are attached to the underside of the breech block 5, as best shown in FIGS. 3 and 4. The lower ends of the levers 15 and 16 are secured to respective torsionbar springs 13 and M which are positively, i.e.,

force-transmittingly, coupled to the breech 4. These torsion-bar springs are put under stress as the breech,

block is raised in the course of the counter-recoil of the barrel so that the closing action, which takes place automatically under the influence of the weight of the breech block 5, is helped by the stressed torsion-bar springs l3, 14. This is particularly advantageous when the breech block is in the process of being closed while the gun barrel is in elevated position, because in that position the breech block will not be free to drop under the influence of its own weight but will slide along the surfaces 4a.

a The above-described mechanism operatesas follows:

In the position shown in FIGS. 1 and 2, the breech block 5 is open and the barrel has almost completed its counter-recoil movement into the extreme forward or firing position. At this point, the rollers 6, which act as cam followers, engage the top of the upwardly rising cam surface section 8b. The forward movement of the barrel is stopped for a short time and the shell 12, which at this time is resting on a support 11 of an automatic loading mechanism, is rammed home into the breech end of the barrel. Inasmuch as the breech end of the bore is freely accessible, as best shown in FIG. 4, the support 11 can be moved directly against the breech opening, whereupon all that needs to be done is to insert the shell and to supply the propellant charge. The remaining steps are carried out by a conventional mechanism (not shown) whereupon the barrel continues its forward movement and the rollers 6 move over the cam section 80. This allows the breech block 5 to drop down and to close off the breech end of the bore. The piece is now ready to be fired; this can be done either automatically or by manually selecting the instant at which the propellant charge is ignited.

The firing of the shell 12 produces a recoil which causes the barrel 1 together with the breech block 5 to be moved rearwardly at high speed. In the course of this rearward movement, the rollers 6 move through the guide grooves 9 the sub-sections 8d being engaged by the rollers and raised during part of this movement until they come to rest on the level sections 8a.

Prior to firing, the support 11 will have been moved rearwardly and a fresh shell 12 will have been placed on the support. After the recoil, the cocked recuperator will, without interruption, advance the barrel 1 and the breech block 5. In practice, the support 11 may be operatively associated with the recuperator in such a way as to be advanced together with the barrel.

In the course of the counter-recoil movement, which comes to a temporary end at the instant at which the guide rollers 6 come to lie on the highest point of the cam section 8b, the breech block is in its fully open position, so that the fresh cartridge shell and a new propellant charge can be loaded into the breech, it being evident that, instead of providing such separate-type ammunition, i.e., a shell requiring a separate charge, the ammunition can itself be of the fixed-type, i.e., a shell which contains the propellant charge. But even in the case of separate-type ammunition it has been found that a piece according to the present invention, handling a 15 cm shell, can be re-loaded within 4 seconds, including the recoil and counter-recoil; this, in comparison to conventional pieces of the same or similar caliber which incorporate a sliding square-wedge breech block arrangement, which, if equipped with an automatic loading mechanism require almost 8 seconds 1. In a piece of ordnance, the combination which comprises:

a. a barrel having a breech with a breech opening;

b. a breech block for closing said breech opening of said barrel, said breech block being mounted on the exterior of said breech for sliding movement relative to said barrel transversely to the axis of said barrel and in the vertical longitudinal central plane of said barrel;

c. a cradle for mounting said barrel and breech block for forward and rearward movement in the direction of said bore axis; and

d. camming means for raising said breech block and thereby uncovering said breech opening during forward movement of said barrel, said camming means including a pair of lateral cam surfaces mounted on said cradle, one on each side of said barrel, and increasing in height in the forward direction, and a pair of cam follower means mounted on opposite sides of said breech block for movement therewith and coacting with the associated one of said lateral cam surfaces.

2. The combination defined in claim 1 wherein said cam follower means comprise two rollers arranged on opposite sides of said breech block.

3. The combination defined in claim 1 wherein each of said cam surfaces has a rear section which is level, an intermediate section which increases in height in the forward direction to cause said breech block to be raised and open said breech opening, and a forward section which drops abruptly in the forward direction to allow said breech block to drop and close said breech opening.

4. The combination defined in claim 3 wherein said camming means further includes a level guide groove associated with each of said cam surfaces through which passes the respective roller during rearward travel of said barrel and breech block, said guide groove having a lower edge which transitions into said rear section of said cam surface.

5. The combination defined in claim 4 wherein said intermediate section of said cam surface includes a subsection which extends from said rear section to a point above the upper edge of said guide groove, said subsection being a swingable switch.

6. The combination defined in claim 5 wherein said subsection is pivotally mounted on said cam surface means and is engaged by the respective roller during rearward movement of said barrel and breech so as to be raised by said roller.

7. The combination defined in claim 1, further comprisingmeans for continually urging said breech block into its closed position, said last-mentioned means include lever means one end of which engages the underside of said breech block and torsion-bar spring means connected to the'other end of said lever means, said torsion-bar spring means being force-transmittingly connected to said breech.

8. The combination defined in claim 7 wherein said lever means include two levers arranged on opposite sides of said breech block and said torsion-bar spring means include two torsion-bar springs each being coupled to a respective one of said levers, said torsion-bar springs extending transversely through said breech and being arranged next to each other and being connected to said breech at their respective opposite ends 9. The combination defined in claim 8 wherein said 

1. In a piece of ordnance, the combination which comprises: a. a barrel having a breech with a breech opening; b. a breech block for closing said breech Opening of said barrel, said breech block being mounted on the exterior of said breech for sliding movement relative to said barrel transversely to the axis of said barrel and in the vertical longitudinal central plane of said barrel; c. a cradle for mounting said barrel and breech block for forward and rearward movement in the direction of said bore axis; and d. camming means for raising said breech block and thereby uncovering said breech opening during forward movement of said barrel, said camming means including a pair of lateral cam surfaces mounted on said cradle, one on each side of said barrel, and increasing in height in the forward direction, and a pair of cam follower means mounted on opposite sides of said breech block for movement therewith and coacting with the associated one of said lateral cam surfaces.
 2. The combination defined in claim 1 wherein said cam follower means comprise two rollers arranged on opposite sides of said breech block.
 3. The combination defined in claim 1 wherein each of said cam surfaces has a rear section which is level, an intermediate section which increases in height in the forward direction to cause said breech block to be raised and open said breech opening, and a forward section which drops abruptly in the forward direction to allow said breech block to drop and close said breech opening.
 4. The combination defined in claim 3 wherein said camming means further includes a level guide groove associated with each of said cam surfaces through which passes the respective roller during rearward travel of said barrel and breech block, said guide groove having a lower edge which transitions into said rear section of said cam surface.
 5. The combination defined in claim 4 wherein said intermediate section of said cam surface includes a sub-section which extends from said rear section to a point above the upper edge of said guide groove, said sub-section being a swingable switch.
 6. The combination defined in claim 5 wherein said subsection is pivotally mounted on said cam surface means and is engaged by the respective roller during rearward movement of said barrel and breech so as to be raised by said roller.
 7. The combination defined in claim 1, further comprising means for continually urging said breech block into its closed position, said last-mentioned means include lever means one end of which engages the underside of said breech block and torsion-bar spring means connected to the other end of said lever means, said torsion-bar spring means being force-transmittingly connected to said breech.
 8. The combination defined in claim 7 wherein said lever means include two levers arranged on opposite sides of said breech block and said torsion-bar spring means include two torsion-bar springs each being coupled to a respective one of said levers, said torsion-bar springs extending transversely through said breech and being arranged next to each other and being connected to said breech at their respective opposite ends.
 9. The combination defined in claim 8 wherein said breech block carries, at its opposite lower edge, rail means which form grooves within which said levers are slidingly received.
 10. The combination defined in claim 3, further comprising means for continually urging said breech block into its closed position, said last-mentioned means include lever means one end of which engages the underside of said breech block and torsion-bar spring means connected to the other end of said lever means, said torsion-bar spring means being force-transmittingly connected to said breech. 